The present invention relates to anti-chipping sheets for protecting various surfaces against the phenomenon in which pebbles, small objects and the like on roads are bounced up by wheels to impinge upon automobile bodies to damage coated surfaces of the bodies while the automobiles are moving.
For exterior trims of automobiles, widely used are steel plates or plastic resin materials that are molded and whose surfaces are covered with a coating or the like. Among them, those on the sides and underside of the automobile bodies are likely to develop scratches, cracks, dents and the like on the coated surfaces of the steel plates and exterior trims due to impingement or the like of hard objects such as rocks bounced up by tires while the automobiles are running.
In order to prevent such scratches, cracks, dents and the like from developing on the surfaces, anti-chipping coating has traditionally been carried out with vinyl chloride-based sols. Such sols may, however, produce dioxin when they are incinerated. Also, coated surface is protected by applying a chipping film of urethane-based substrate covered with fluorine coating. The raw materials and the coating are, however, expensive, thereby rendering the anti-chipping films also expensive. Due to such cost restrictions, they cannot be applied to all portions where scratches, cracks, dents or the like are likely to develop on the surfaces but are often used only partly, suffering from problems substantially (Patent Reference 1).
In order to solve these problems, chipping films whose substrates are made of ionomer and polyolefin-based polymer layers have been proposed as low-priced chipping films that are capable of protecting various surfaces, in particular, preventing scratches, cracks, dents and the like from developing on exterior trims of automobiles, while conforming to asperities and extremities of the applied objects and being applied easily and in a good-looking manner (Patent Reference 2).
Patent Reference 1: Japanese Unexamined Patent Publication Hei 9-277379
Patent Reference 2: WO2007/069330